Detailed Description

These functions provide a variety of logging functions.

The functions use (implicitly) the currently active log target, so their descriptions here may not apply if the log target is not the standard one (installed by wxWidgets in the beginning of the program).

Macros

Functions

This function shows a message to the user in a safe way and should be safe to call even before the application has been initialized or if it is currently in some other strange state (for example, about to crash). More...

Calls wxTraceLevel with printf-style variable argument syntax. Output is directed to the current output stream (see wxDebugContext). The first argument should be the level at which this information is appropriate. It will only be output if the level returned by wxDebugContext::GetLevel is equal to or greater than this value.

Include file:

#include <wx/memory.h>

Function Documentation

void wxLogDebug

(

const char *

formatString,

...

)

The right functions for debug output.

They only do something in debug mode (when the preprocessor symbol WXDEBUG is defined) and expand to nothing in release mode (otherwise).

Include file:

#include <wx/log.h>

void wxLogError

(

const char *

formatString,

...

)

The functions to use for error messages, i.e.

the messages that must be shown to the user. The default processing is to pop up a message box to inform the user about it.

Include file:

#include <wx/log.h>

void wxLogFatalError

(

const char *

formatString,

...

)

Like wxLogError(), but also terminates the program with the exit code 3.

Using abort() standard function also terminates the program with this exit code.

Messages logged by this function will appear in the statusbar of the frame or of the top level application window by default (i.e.

when using the second version of the functions).

If the target frame doesn't have a statusbar, the message will be lost.

Include file:

#include <wx/log.h>

void wxLogStatus

(

const char *

formatString,

...

)

void wxLogSysError

(

const char *

formatString,

...

)

Mostly used by wxWidgets itself, but might be handy for logging errors after system call (API function) failure.

It logs the specified message text as well as the last system error code (errno or GetLastError() depending on the platform) and the corresponding error message. The second form of this function takes the error code explicitly as the first argument.

Notice that the use of trace masks is not recommended any more as setting the log components (please see Log Messages Selection) provides a way to do the same thing for log messages of any level, and not just the tracing ones.

Like wxLogDebug(), trace functions only do something in debug builds and expand to nothing in the release one. The reason for making it a separate function is that usually there are a lot of trace messages, so it might make sense to separate them from other debug messages.

Trace messages can be separated into different categories; these functions in facts only log the message if the given mask is currently enabled in wxLog. This lets you selectively trace only some operations and not others by enabling the desired trace masks with wxLog::AddTraceMask() or by setting the WXTRACE environment variable.

The predefined string trace masks used by wxWidgets are:

wxTRACE_MemAlloc

Trace memory allocation (new/delete)

wxTRACE_Messages

Trace window messages/X callbacks

wxTRACE_ResAlloc

Trace GDI resource allocation

wxTRACE_RefCount

Trace various ref counting operations

wxTRACE_OleCalls

Trace OLE method calls (Win32 only)

Include file:

#include <wx/log.h>

void wxLogTrace

(

wxTraceMask

mask,

const char *

formatString,

...

)

Like wxLogDebug(), trace functions only do something in debug builds and expand to nothing in the release one.

The reason for making it a separate function is that usually there are a lot of trace messages, so it might make sense to separate them from other debug messages.

This version of wxLogTrace() only logs the message if all the bits corresponding to the mask are set in the wxLog trace mask which can be set by calling wxLog::SetTraceMask(). This version is less flexible than wxLogTrace(const char*,const char*,...) because it doesn't allow defining the user trace masks easily. This is why it is deprecated in favour of using string trace masks.

The following bitmasks are defined for wxTraceMask:

wxTraceMemAlloc

Trace memory allocation (new/delete)

wxTraceMessages

Trace window messages/X callbacks

wxTraceResAlloc

Trace GDI resource allocation

wxTraceRefCount

Trace various ref counting operations

wxTraceOleCalls

Trace OLE method calls (Win32 only)

Include file:

#include <wx/log.h>

void wxLogVerbose

(

const char *

formatString,

...

)

For verbose output.

Messages generated by these functions are suppressed by default, even if the log level is higher than wxLOG_Info and need to be explicitly activated by calling wxLog::SetVerbose().

Notice that this is done automatically by wxWidgets, unless the standard command line handling is overridden, if --verbose option is specified on the program command line, so using these functions provides a simple way of having some diagnostic messages not shown by default but which can be easily shown by the user if needed.

Include file:

#include <wx/log.h>

void wxLogWarning

(

const char *

formatString,

...

)

For warnings - they are also normally shown to the user, but don't interrupt the program work.

This function shows a message to the user in a safe way and should be safe to call even before the application has been initialized or if it is currently in some other strange state (for example, about to crash).

Under Windows this function shows a message box using a native dialog instead of wxMessageBox() (which might be unsafe to call), elsewhere it simply prints the message to the standard output using the title as prefix.

Parameters

title

The title of the message box shown to the user or the prefix of the message string.

Takes printf() style variable argument syntax. Output is directed to the current output stream (see wxDebugContext). The first argument should be the level at which this information is appropriate. It will only be output if the level returned by wxDebugContext::GetLevel() is equal to or greater than this value.